A suspended ceiling is normally used in commercial and industrial buildings, and includes a ceiling grid framework configured to have a plurality of grids which can be used to support ceiling panels, lighting fixtures, or other devices (such as air conditioning vent/intake covers, etc.). Sometimes, the mounting of lighting fixtures on the grids is restricted by other devices or the building structure, e.g., concrete beams of the building. Thus, in a room space under the ceiling grid framework, there might be relatively dark areas.